// register class VR128 by method 'constrainOperandRegClass' which is
// directly called by 'fastEmitInst_ri'.
// Instruction VCVTPS2PHrr takes an extra immediate operand which is
- // used to provide rounding control.
- InputReg = fastEmitInst_ri(X86::VCVTPS2PHrr, RC, InputReg, false, 0);
+ // used to provide rounding control: use MXCSR.RC, encoded as 0b100.
+ // It's consistent with the other FP instructions, which are usually
+ // controlled by MXCSR.
+ InputReg = fastEmitInst_ri(X86::VCVTPS2PHrr, RC, InputReg, false, 4);
// Move the lower 32-bits of ResultReg to another register of class GR32.
ResultReg = createResultReg(&X86::GR32RegClass);
define i16 @test_fp32_to_fp16(float %a) {
; CHECK-LABEL: test_fp32_to_fp16:
-; CHECK: vcvtps2ph $0, %xmm0, %xmm0
+; CHECK: vcvtps2ph $4, %xmm0, %xmm0
; CHECK-NEXT: vmovd %xmm0, %eax
; CHECK-NEXT: retq
entry: